Motor runaway when restart FLB2360T controller

Hi.
We are currently developing an AGV that following people using the FLB2360T controller with two motors. The front bumper is designed to drop the main battery according to the safety recommendation on manual so that it will stop in an emergency that hits a person.

When the motor is operated with the above configuration, the power of the controller is turned off due to the emergency stop of the bumper, and after restarting controller, the motor runaway or does not work even if a command is sent. After that, I restarted the controller again, it will work normally or be in a similar state.

Currently, the control is operated by closed loop control. Considering the possibility that the encoder signal has not arrived, I sent the "? S nn" command after "! S nn", a loop error exceeding 4000 is recorded. So I think it means the encoder is well.

So do you know what my problem is? How can I fix it?
thank you very much.

I have tried some commands that may be relevant to the problem.
Then, after restarting, I ran "% CLMOD 2" and "% CLMOD 3". The frequency of motor runaway has been reduced.
However, it has not been completely fixed yet.